CN102158601A - Internet of things telephone capable of remotely reading meter - Google Patents
Internet of things telephone capable of remotely reading meter Download PDFInfo
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- CN102158601A CN102158601A CN2011100794943A CN201110079494A CN102158601A CN 102158601 A CN102158601 A CN 102158601A CN 2011100794943 A CN2011100794943 A CN 2011100794943A CN 201110079494 A CN201110079494 A CN 201110079494A CN 102158601 A CN102158601 A CN 102158601A
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Abstract
The invention provides an Internet of things telephone capable of remotely reading a meter, which belongs to the technical field of telecom. A wireless communication module and a voice module are arranged, a telephone line is utilized as a signal transmission antenna, data on a household electricity meter, a household gas meter and a household water meter can be automatically read in a household based on the conventional telephone by utilizing a short-range wireless communication technology, the read data is transmitted to a centralized controller module in the Internet of things telephone for processing, and information is fed back to an active querier in form of a voice information by a conventional public telephone network. The Internet of things telephone combines the short-range wireless communication module and a conventional household telephone to realize remote meter reading and remote control. Due to the extremely high popularizing rate of the telephone, the short-range wireless communication technology is flexible and convenient to distribute in the household.
Description
Technical field
The present invention relates to a kind of Internet of Things phone that can be used for remote meter reading, affiliated telecommunication technology field.
Background technology
The high speed development of computer technology, communication and microelectric technique, Internet technology, radio-frequency (RF) tag (RFID) technology, global positioning system (GPS) and digital earth broad application have been promoted, and the fast development of wireless network and wireless sensor network (WSN) research, tremendous economic that internet, applications produced and social benefit have been deepened the understanding of people to the informationization effect.But also must import and manage about the collection of human society, culture, science and technology and economic information on the Internet now by the people.In order to adapt to the demand of economic globalization, if RFID technology, WSN technology, GPS technology, digital earth technology and the Internet are combined if people imagine from the angle of information flow, just can expand the coverage of the Internet to " thing " from " people ", just can and obtain the information of relevant logistics by RFID technology, WSN technology and the collection of GPS technology, by the Internet realize to worldwide logistics information fast, accurately identification and all-the-way tracking, this technology is exactly a technology of Internet of things.
In the automatic electric kilowatt meter reading-out system of long distance wireless that China has mainly used, be divided into following several by the difference of bottom communication modes:
1) mode by power carrier communication realizes that the long-range electricity this communication modes of checking meter does not need investment to lay communication line, the input of can economizing on the use of funds, also have the little characteristics of maintenance, especially in recent years the successful Application of spread spectrum technic, make the low-voltage power carrier communication begin to be applied in the automatic electric kilowatt meter reading-out system of long distance wireless, but at present power carrier communication have obvious deficiency: mainly to show as strong noise, Low ESR, loss is big, fluctuation is big, be subject to external interference.Some low-voltage networks in China, load variations is big and lack regularity, and various interference are very serious, and the broadband communication technology is applied to automatic electric kilowatt meter reading-out system, the effect that does not also obtain in China at present.
2) realize that by RS485 wire communication net the long-range electricity EIA RS485 that checks meter is the V.11/X.27 compatible balanced type electrical characteristic standard of standardization CCITT, RS485 wire communication Netcom crosses on the interconnecting cable of a pair of balance and to transmit differential signal and to realize transfer of data in the mode that receiving terminal carries out signal decision, it is strong that this network has an antijamming capability, long transmission distance (1200M), the characteristics of data rate height (100kb/s), but because it is a cable network, need the special transmission equipment of laying, this needs extra investment cost, it uses twisted-pair feeder as network-bus in addition, support 128 nodes at most, can not satisfy the more user's of some network nodes needs, it is mainly used in a small amount of high-grade biotope in China.
3) realize that by GPRS wireless telecommunications net the long-range electricity GPRS that checks meter is that the English of GPRS is called for short, GPRS remote auto electricity kilowatt meter reading-out system is to utilize the GPRS public network to realize the transmission of ammeter data, it uses the Internet resources of GPRS as the user of GPRS, GPRS is as the transmission network of a maturation, it is big that it has transfer rate, frequency efficiency height, transfer of data have the characteristics of reliability assurance, can satisfy the needs of remote auto electricity kilowatt meter reading-out system.But because the GPRS terminal that is installed on each ammeter costs an arm and a leg, domestic price is between 600-1500 unit, the GPRS power consumption of terminal is also bigger, and come into operation from the automatic electric kilowatt meter reading-out system of GPRS wireless remote, the ammeter user just needs to pay certain expense by data traffic to GPRS operator always, and comprehensively its installation, maintenance and use cost have surpassed manual metering to a certain extent on the contrary, therefore, can not used widely.At present, to fail wide popularization and application be the communication scheme of its system bottom to the main bottleneck in power supply enterprise's counting cost by gas meter to remote auto electricity kilowatt meter reading-out system---promptly the data of each ammeter are sent to this process of processing terminal.
At present, the popularity rate of home telephone has reached quite high stage.Utilize existing public phone network to carry out Long-distance Control or remote meter reading is an economy, effectively means.Traditional phone is mainly used in interpersonal communication, perhaps black phone is carried out the existing public telephone network of part renovation and utilization, carries out simple Long-distance Control.
Now, the develop rapidly of short-distance wireless communication technology is at Smart Home, and huge contribution has been made in aspects such as remote monitoring.In short-distance wireless communication technology, the ZigBee technology has absolute advantage.The Zigbee transmission range is tens of rice, and using frequency range is free 2.4GHz and 900MHz frequency range, and transmission rate is 20kbps to 250kbps.BobHeile thinks that with respect to existing various wireless communication technologys, the low-power consumption of ZigBee technology, low rate are best suited for the standard as sensor network, and this will become the main developing direction of following Zigbee technology.In addition, characteristics such as the Zigbee cost is low, simple in structure, power consumption is little, make the network utilize the Zigbee technology to form possess power saving, reliable, many advantages such as cost is low, capacity is big, safety, self-healing property are strong, more flexible, free when networking and the selection network path based on the mesh network structure of Zigbee technology.ZigBee is a kind of low-power consumption based on IEEE802.15.4, low transmission rate, the simple short-distance wireless communication technology of framework, and it is at automation field, and the application in Smart Home field just more and more causes attracting attention of industry.
Summary of the invention
Technical problem
Technical problem to be solved by this invention provides a kind of Internet of Things phone that can be used for remote meter reading, can realize functions such as remote inquiry, control, can accurately obtain the data of domestic consumer's water, electricity, gas three tables.
Technical scheme
The present invention adopts following technical scheme for solving the problems of the technologies described above:
A kind of Internet of Things phone that can be used for remote meter reading, comprise home telephone, be attempted by the Centralized Controller on the phone, described Centralized Controller comprises wireless communication module, voice module, ring detecting circuit, DTMF decoder module, auto-pickup circuit, microprocessor module;
Wherein: microprocessor module links to each other with wireless communication module, voice module, ring detecting circuit, DTMF decoder module, auto-pickup circuit respectively;
Described wireless communication module and tame electricity consumption, gas, water three table nodes carry out data communication.
Further, can be used for the Internet of Things phone of remote meter reading, described wireless communication module utilizes telephone wire to be used as reception antenna, can increase receiving sensitivity, increases transmission range, reduces transmitting power.
Further, can be used for the Internet of Things phone of remote meter reading, the CC2420 chip that described wireless communication module adopts band ZigBee agreement to support.
Further, can be used for the Internet of Things phone of remote meter reading, described DTMF decoder module adopts the MT8870 chip, and the STD signal output part of described MT8870 chip connects the INT0 pin of microprocessor module.The DTMF signal that remote subscriber sends, after the stopping direct current effect of electric capacity, its relevant pin receives the dual-tone multifrequency pulse signal from telephone set, and this touch-tone signal is exported corresponding 8421 yards through computing at its data output end; The STD output signal of described MT8870 connects the INT0 pin of microprocessor module, after MT8870 obtains effective touch-tone signal, the STD level is uprised by low, after CPU detects, the indication single-chip microcomputer receives effective binary code, and invalid double-audio signal to be the STD end that can not cause MT8870 change.
A kind of method of work that can be used for the Internet of Things phone of remote meter reading comprises the steps,
Step 1, when ring detecting circuit has detected the signal incoming call, send a signal to microprocessor module, microprocessor module receives the signal that ring detecting circuit sends, call the auto-pickup circuit, the process of simulation plain old telephone off-hook connects with call initiator, call the voice messaging of having preserved in the voice module simultaneously, send voice suggestion to call initiator;
Step 2, call initiator sends request of data by telephone key-press to microprocessor module, when microprocessor module receives the request of data of calling party transmission, call the DTMF decoder module, by the DTMF decoder module with the decoding of the push button signalling that receives after, the key assignments that decoding is obtained feeds back to microprocessor module;
Step 3 adopts microprocessor module to activate wireless communication module, and the wireless communication module with family expenses three tables by wireless communication module communicates, and finishes corresponding data acquisition;
Step 4, wireless communication module feeds back to microprocessor with the data that collect by data-interface, microprocessor module is according to the data that obtain from wireless communication module, call voice module the data that collect are fed back to call initiator with the form of voice by public phone network, be all over up to the call initiator task requests;
Step 5, microprocessor module reactivates ring detecting circuit, and other modules are set to holding state, wait call request next time.
Described wireless communication module and tame electricity consumption, gas, water three table nodes can carry out normal data communication, the voice messaging that records is left in the speech chip, the auto-pickup function is provided, when call, the caller can finish inquiry, controlled function under voice suggestion.
Beneficial effect
The present invention utilizes existing public phone network that long-distance meter-reading system is installed to every household, need not set up communication line in addition, realize remote inquiry, functions such as control, it is bigger than the reliability of power carrier transmission data to transmit data by public telephone network, real-time image data, administrative staff can accurately obtain the data of domestic consumer's water, electricity, gas table; And the present invention transforms existing home phone number, and development cost is low, can reduce investment cost, and feasibility is very high.
Description of drawings
Fig. 1 is a structured flowchart of the present invention;
Fig. 2 is dtmf signal decoder module figure of the present invention;
Fig. 3 is a method of work schematic diagram of the present invention.
Embodiment
Embodiment of the present invention one: utilize in the family existing phone to transform, on original telephone line and connect a Centralized Controller, make improved phone become core component in the long-distance meter-reading system.As shown in Figure 1, Centralized Controller mainly comprises wireless communication module, voice module, ring detecting circuit, DTMF decoder module, auto-pickup circuit, microprocessor module, and microprocessor module links to each other with wireless communication module, voice module, ring detecting circuit, dual tone multi-frequency dtmf decoder module, auto-pickup circuit respectively.
When phone ringing, produce the voltage signal that exchanges 48 V on its circuit, utilize electric capacity to block direct current, only allow bell signal (about 30 Hz) pass through, this moment, the photoelectrical coupler conducting made the current potential step-down of the relevant pin of single-chip microcomputer, thereby made single-chip microcomputer detect bell signal.After processor detected 4 rings, CPU control relay closure made the resistance that inserts 200 Ω on the telephone wire by peripheral circuit, thereby switch is thought phone off-hook.
Behind phone incoming call and remote telephone controller off-hook, operating personnel just can be under the prompting of voice warning circuit, to water, and electricity, the gas meter data are inquired about.Sound circuit adopts voice recording and playback ic ISD4002, operational order is sent into by serial communication interface, and chip adopts many level direct modeling amount memory technology, and each sampled value directly is stored in the interior flash memory of sheet, therefore can be very true, realize voice, music, tone and effect sound more naturally.After the voice messaging of needs promptings is entered into chip by section, under the control of CPU, the information of typing is exported by audio output, after audio-frequency power amplifier LM386 amplifies, be transported on the telephone line then.
Electric capacity of series connection in the middle of telephone wire and receiver.The voltage that this electric capacity has been isolated telephone wire comprises ring, can not damage receiver like this.High pass filter can be used for the following signal of filtering short frequency.Can resist interference like this, and the audio frequency on the telephone wire is presented a kind of high impedance, the unlikely balance that influences telephone wire from local medium wave radio station.Low pass filter can be used for the above signal of filtering short frequency.Can resist interference like this, use two kinds of filters simultaneously, the output of one of them can be connected in the input of second filter from FM radio station and TV signal.
The radio communication of setting up between the ZigBee adapter of family's Internet of Things telephony hardware platform and terminal equipment is connected, and is based on wirelessly to substitute wired and wireless channel that set up connects, it and actual not too big difference connected in series.Like this, utilize the previous ZigBee kit of transplanting, after finishing on the home gateway hardware platform pairing between the wireless adapter and terminal equipment and being connected, just can operate the connected in series of this wireless channel, realize communication and control in this locality terminal equipment in the mode of operating equipment file.The content that mainly comprises two aspects: the control command that to be administrative staff send by the Internet of Things phone will send to terminal equipment by the ZigBee module, and another status data that is terminal equipment feeds back to family's Internet of Things phone also will send to the Internet of Things phone by the mode of ZigBee.Wireless communication module adopts the CC2420 chip that band ZigBee agreement is supported among the design.CC2420 is the low cost of a compatible 2.4 GHz IEEE802.15.4 standards of Chipcon company release, the active radio frequency chip of low-power consumption.It has realized the physical layer (PHY) and the intermediate accesses key-course (MAC) of ZigBee agreement.This chip adopts 0.18 μ m CMOS technology, monolithic integrated level height, and volume is little, and overall dimension has only 7 m * 7 m.The inner 1.8 V operating voltages of using, low in energy consumption, outside 3.3 V that use, integrated direct current stabilizer can become 1.8 V to the voltage transitions of 3.3 V on the sheet, is suitable for battery powered apparatus.In addition, CC2420 has fully-integrated voltage controlled oscillator, only needs considerably less peripheral circuits such as antenna, 16 MHz crystal just can work on the 2.4GHz frequency range.The interface of CC2420 and microprocessor is by the register mode area and the memory block of SPI interface (SI, SO, SCLK and CSn) visit CC2420 inside, and high workload speed can reach 10 MHz.
Embodiment of the present invention two, from existing dual-tone multifrequency phone condensed design a ZigBee of having function can realize auto-pickup, and provide the Internet of Things phone of simplifying function of respective service for the active speaker by voice suggestion.
As shown in Figure 2, the dtmf signal decoding circuit is born by MT8870.The DTMF signal that remote subscriber sends, after the stopping direct current effect of electric capacity, its relevant pin receives the dual-tone multifrequency pulse signal from telephone set, and this touch-tone signal is exported corresponding 8421 yards through computing at its data output end.In order to make single-chip microcomputer obtain valid data, the STD output signal of MT8870 connects CPU's/the INT0 pin, after MT8870 obtains effective touch-tone signal, the STD level is uprised by low, after CPU detects, the indication single-chip microcomputer receives effective binary code, and invalid double-audio signal (telephone line noise, people's voice signal etc.) to be the STD end that can not cause MT8870 change.Wherein, the electric capacity that is connected on the power supply place has jamproof effect.
Ring detecting circuit serves as main formation with optocoupler 817, when bell signal, ringing-current enters 817 input pins and output pulse square wave signal, deliver to single-chip microcomputer external interrupt pin, because voice signal and double-audio signal voltage are far below ringing signal voltage, this circuit can not cause erroneous judgement.
Though this Internet of Things phone can not initiatively make a call, can realize the needed actual functional capability of remote meter reading.
Above-mentioned is the hardware designs of this Internet of Things phone, the concrete method of work of the present invention is as follows: as Fig. 1, shown in 3, step 1, under the normal state, this Internet of Things phone is in holding state, when ring detecting circuit has detected the signal incoming call, send a signal to processor, processor receives the signal that ring detecting circuit sends, and calls automatically and answers circuit, the process of simulation plain old telephone off-hook, connect with active call side, call the voice messaging of having preserved in the voice module simultaneously, select suitable voice signal to feed back to call initiator, send voice suggestion to call initiator by telephone wire; Step 2, when active call person receives voice suggestion, select corresponding button, when microprocessor module receives the key information of calling party transmission, call the DTMF decoder module, after by the DTMF decoder module push button signalling that receives being decoded, the key assignments that decoding is obtained feeds back to microprocessor module, microprocessor module goes to carry out the task requests that corresponding action is finished the caller according to the key assignments that obtains; Step 3, when the caller need gather the data that family expenses three are shown, then microprocessor module activates wireless communication module, send corresponding instruction by interface with wireless communication module, connect by the wireless communication module on wireless communication module on the phone and the table, finish corresponding data acquisition; Step 4, wireless communication module feeds back to processor with the data that collect by data-interface, microprocessor is according to the data that obtain from wireless communication module, after the suitable voice messaging of having stored that calls voice module is simultaneously handled, the data that collect are fed back to active call person with the form of voice by public phone network, be all over up to the call initiator task requests, and detect initiatively on-hook of calling party; Processor reactivates ring detecting circuit, and other modules are set to holding state, wait call request next time.
Claims (5)
1. Internet of Things phone that can be used for remote meter reading, it is characterized in that: comprise home telephone, be attempted by the Centralized Controller on the phone, described Centralized Controller comprises wireless communication module, voice module, ring detecting circuit, DTMF decoder module, auto-pickup circuit, microprocessor module;
Wherein: microprocessor module links to each other with wireless communication module, voice module, ring detecting circuit, DTMF decoder module, auto-pickup circuit respectively;
Described wireless communication module and tame electricity consumption, gas, water three table nodes carry out data communication.
2. according to the described a kind of Internet of Things phone that can be used for remote meter reading of claim 1, it is characterized in that: described wireless communication module utilizes telephone wire to be used as reception antenna.
3. according to the described a kind of Internet of Things phone that can be used for remote meter reading of claim 1, it is characterized in that: the CC2420 chip that described wireless communication module adopts band ZigBee agreement to support.
4. according to the described a kind of Internet of Things phone that can be used for remote meter reading of claim 1, it is characterized in that: described DTMF decoder module adopts the MT8870 chip, and the STD signal output part of described MT8870 chip connects the INT0 pin of microprocessor module.
5. method of work that can be used for the Internet of Things phone of remote meter reading, its spy is: comprises the steps,
Step 1, when ring detecting circuit has detected the signal incoming call, send a signal to microprocessor module, microprocessor module receives the signal that ring detecting circuit sends, call the auto-pickup circuit, the process of simulation plain old telephone off-hook connects with call initiator, call the voice messaging of having preserved in the voice module simultaneously, send voice suggestion to call initiator;
Step 2, call initiator sends request of data by telephone key-press to microprocessor module, when microprocessor module receives the request of data of calling party transmission, call the DTMF decoder module, by the DTMF decoder module with the decoding of the push button signalling that receives after, the key assignments that decoding is obtained feeds back to microprocessor module;
Step 3 adopts microprocessor module to activate wireless communication module, and the wireless communication module with family expenses three tables by wireless communication module communicates, and finishes corresponding data acquisition;
Step 4, wireless communication module feeds back to microprocessor with the data that collect by data-interface, microprocessor module is according to the data that obtain from wireless communication module, call voice module the data that collect are fed back to call initiator with the form of voice by public phone network, be all over up to the call initiator task requests;
Step 5, microprocessor module reactivates ring detecting circuit, and other modules are set to holding state, wait call request next time.
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| CN201110079494.3A CN102158601B (en) | 2011-03-31 | 2011-03-31 | Internet of things telephone capable of remotely reading meter |
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| CN201110079494.3A CN102158601B (en) | 2011-03-31 | 2011-03-31 | Internet of things telephone capable of remotely reading meter |
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| CN109756636A (en) * | 2017-11-08 | 2019-05-14 | 中华电信股份有限公司 | System and method based on answering bell of incoming call monitoring Internet of Things equipment state |
| CN109862543A (en) * | 2017-11-30 | 2019-06-07 | 南京德朔实业有限公司 | The adapter and wireless connection method being wirelessly connected are established with terminal |
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